The present invention relates broadly to vehicle air conditioning systems. More specifically, the present invention relates to an improved auxiliary air conditioning structure which can be retrofitted into an existing van, camper, or other recreational vehicle ("RV") without detracting from the body design.
In the prior art known to us, a wide variety of air conditioning systems have been proposed for use in recreational vehicles. The majority of such systems involve mounting on the vehicle roof, and many are powered by external electrical sources when parked. Representative of such systems are U.S. Pat. No. 3,984,224, issued Oct. 5, 1976 to Dawkins; U.S. Pat. No. 4,134,275, issued to Erickson Jan. 16, 1979; and, U.S. Pat. No. 4,201,064, issued May 6, 1980 to Krug.
Numerous disadvantages are associated with the roof-mounted systems known to us. Structurally, many prior art systems are bulky and cumbersome. Typically, they are mounted with efforts and attention directed to functional rather than aesthetic considerations. As a result, the units tend to detract from the overall appearance of the vehicles, creating an unattractive, "top-heavy" profile.
Also, known prior art systems often make it more difficult to maneuver the vehicle. Roof mounted units can raise the height of the vehicle too much, lowering clearance. Interference with low hanging branches, for example, often results. Narrow passageways are typically found in campsites, recreational parks, airport entry ramps, home carports and garages. Travel vans must adequately traverse such restricted corridors, and they should maintain adequate visibility as well.
Further, seals between the roof panel and top-mounted units often deteriorate, resulting in air and water leakage. Air leaks increase noise levels and affect temperature control, thereby reducing passenger comfort. Water leaks may cause serious damage to the vehicle's interior and electrical system.
The operating efficiency of the vehicle also may be deleteriously affected by the additional bulk and weight of such prior art roof-mounted systems. Roof mounted units impede the air stream over the vehicle, increasing wind drag and reducing gas mileage. Fuel consumption is generally increased due to added weight and air resistance. In response to this problem, some reduced-profile units have been proposed in the prior art, such as Ferdows, U.S. Pat. No. 4,607,497 issued Aug. 26, 1986 and Armbruster, U.S. Pat. No. 4,217,764, issued Aug. 19, 1980.
As a rule, the prior art air conditioning systems known to us heavily tax the vehicle electrical system. In some systems, such as Harr U.S. Pat. No. 4,271,677 issued Jun. 9, 1981, auxiliary motors and generators are provided to correct this situation. However, such units add more weight and bulk.
Finally, the roof-mounted systems present difficulties when service is required. The servicing operator must position himself either on the vehicle roof and/or within the passenger compartment, neither site providing space for safe and comfortable access to the unit. An additional inconvenience is presented because the operator must take care to keep the vehicle interior covered to prevent material damage from footprints, falling components, fluid spills, or the like. Moreover, if the unit must be removed, the seals will be damaged and improper alignment of the unit may occur during reinstallation.
It has been proposed in the prior art to mount one or more components of the air conditioning system to parts of the vehicle body other than the roof. For example, U.S. Pat. No. 3,855,814 issued to Eubank on Dec. 24, 1974 teaches an air conditioning unit which mounts on the sidewall or on the drawbar of a camper trailer. The aforedescribed mounting affords convenient access for repairs and greatly reduces the risk that the unit will structurally damage the vehicle. However, it is impractical for use on self-propelled vehicles such as vans and recreational vehicles. The Ferdows unit of U.S. Pat. No. 4,607,497 comprises a roof-mounted unit having a separate compressor mounted to the rear of the vehicle. The unit is specifically adapted for large vehicles such as buses and the like.
Thus an auxiliary air conditioning system powered from an outside source such of A.C. electricity typically found in campgrounds, RV parks, and the like, which efficiently delivers a quiet stream of cooled air throughout the vehicle interior with a minimum of parts and without interfering with preexisting vehicle, structure is desired. No prior art air conditioning system known to us adequately addresses the goals of operational efficiency, convenience, cooperation with preexisting parts, and functional attractiveness.